All I can say is that I see 'stars' on a regular basis, whether I'm pregnant or not. I tend to have low blood pressure and it often happens when I'm warm or tweek my neck in a certain way (I think the blood flow must get cut off for a moment). I've talked to many doctors about it and it always gets passed off as normal.
Anyway, it could be worth calling about since you're having some other high-risk issues.. but it's probably nothing.
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